Julien Roger1, Anthony Viste2, Maxime Cievet-Bonfils3, Jean-Pierre Pracros4, Sébastien Raux3, Franck Chotel3. 1. Department of paediatric orthopaedic surgery, hôpital femme-mère-enfant de Lyon, hospices civils de Lyon, université Claude-Bernard Lyon 1, 69500 Bron, France. Electronic address: jux.roger@gmail.com. 2. Department of orthopaedic surgery, hospices civils de Lyon, centre hospitalier Lyon Sud, 69310 Pierre-Bénite, France. 3. Department of paediatric orthopaedic surgery, hôpital femme-mère-enfant de Lyon, hospices civils de Lyon, université Claude-Bernard Lyon 1, 69500 Bron, France. 4. Department of radiology, hôpital femme-mère-enfant de Lyon, hospices civils de Lyon, université Claude-Bernard Lyon 1, 69500 Bron, France.
Abstract
BACKGROUND: The medial patello-femoral ligament (MPFL) is a major patellar stabiliser whose reconstruction in adults involves graft fixation within a femoral tunnel. In skeletally immature patients, in contrast, the graft is fixed to the soft tissues to allow normal growth. The primary objective of this prospective study was to perform computed tomography (CT) and magnetic resonance imaging (MRI) assessments of medium-term correction of patellar tilt and of the axial patellar engagement index (AEI) after a paediatric variant of MPFL reconstruction in skeletally immature patients. HYPOTHESIS: MPFL reconstruction, performed alone or combined with other procedures in skeletally immature patients, decreases patellar tilt and improves the AEI. MATERIAL AND METHODS: Eighteen children and adolescents with a median age of 14.6 years (range, 8-17 years) who underwent MPFL reconstruction on 20 knees were included in this prospective observational study. A double-strand gracilis tendon graft passed through the medial collateral ligament was used. MPFL reconstruction was performed alone in 13 knees and was combined with lateral retinaculum release, tibial tuberosity translation, and/or trochleoplasty in 7 knees. Patellar tilt and AEI values determined on preoperative and post-operative imaging studies with the quadriceps relaxed and contracted were compared. A physical examination was also performed. RESULTS: From baseline to last follow-up after a mean of 43 months (range, 24-63 months), patellar tilt decreased from 20° preoperatively to 9° with the quadriceps relaxed and from 33° to 15.4° with the quadriceps contracted. The AEI increased from 0.78 at baseline to 0.93 at last follow-up. No dislocation or subluxation recurrences were recorded during follow-up. DISCUSSION: The patellar tilt and AEI improvements seen after paediatric MPFL reconstruction confirm the study hypothesis. This is the first prospective study of patellar position in the axial plane as assessed by CT and MRI after paediatric MPFL reconstruction. In everyday clinical practice, 3D assessments of patellar tilt and the AEI should be performed to evaluate correction of the abnormalities. LEVEL OF EVIDENCE: II, non-randomised prospective observational study.
BACKGROUND: The medial patello-femoral ligament (MPFL) is a major patellar stabiliser whose reconstruction in adults involves graft fixation within a femoral tunnel. In skeletally immature patients, in contrast, the graft is fixed to the soft tissues to allow normal growth. The primary objective of this prospective study was to perform computed tomography (CT) and magnetic resonance imaging (MRI) assessments of medium-term correction of patellar tilt and of the axial patellar engagement index (AEI) after a paediatric variant of MPFL reconstruction in skeletally immature patients. HYPOTHESIS: MPFL reconstruction, performed alone or combined with other procedures in skeletally immature patients, decreases patellar tilt and improves the AEI. MATERIAL AND METHODS: Eighteen children and adolescents with a median age of 14.6 years (range, 8-17 years) who underwent MPFL reconstruction on 20 knees were included in this prospective observational study. A double-strand gracilis tendon graft passed through the medial collateral ligament was used. MPFL reconstruction was performed alone in 13 knees and was combined with lateral retinaculum release, tibial tuberosity translation, and/or trochleoplasty in 7 knees. Patellar tilt and AEI values determined on preoperative and post-operative imaging studies with the quadriceps relaxed and contracted were compared. A physical examination was also performed. RESULTS: From baseline to last follow-up after a mean of 43 months (range, 24-63 months), patellar tilt decreased from 20° preoperatively to 9° with the quadriceps relaxed and from 33° to 15.4° with the quadriceps contracted. The AEI increased from 0.78 at baseline to 0.93 at last follow-up. No dislocation or subluxation recurrences were recorded during follow-up. DISCUSSION: The patellar tilt and AEI improvements seen after paediatric MPFL reconstruction confirm the study hypothesis. This is the first prospective study of patellar position in the axial plane as assessed by CT and MRI after paediatric MPFL reconstruction. In everyday clinical practice, 3D assessments of patellar tilt and the AEI should be performed to evaluate correction of the abnormalities. LEVEL OF EVIDENCE: II, non-randomised prospective observational study.
Authors: Riccardo D'Ambrosi; Katia Corona; Paolo Capitani; Gianluca Coccioli; Nicola Ursino; Giuseppe Maria Peretti Journal: Children (Basel) Date: 2021-05-21